Installed net-mgmt/nrpe 4.1.0 pkg. Using /usr/local/etc/nrpe.cfg.sample as a template for the running nrpe.cfg gives this pidfile setting:

pid_file=/var/nrpe.pid

With the included rc.d/nrpe startup script this results in /var/ directory getting chown'd to the nagios user.

Presumably it happens due to this command in rc.d/nrpe nrpe_prestart()

        install -d -o ${nrpe_user:-nagios} ${pidfile%/*}

Which results in:

$ ls -lad /var
drwxr-xr-x  26 nagios wheel 1024 Mar 14 11:39 var
$ ls -la /var/nrpe.pid 
-rw-r--r--  1 root wheel 5 Mar 14 11:39 /var/nrpe.pid

The /var/ ownership change seems bad, and the pidfile location may not be optimal. A couple ideas for a fix:

1) comment-out pid_file from nrpe.cfg and let rc.d/nrpe pidfile logic choose the location
2) set a different path for pid_file in nrpe.cfg, e.g. /var/run/nrpe/nrpe.pid

I'm presently using option #1 and it does avoid the /var/ ownership change.